The present disclosure provides a process for enhancing procatalyst and catalyst properties. The present disclosure provides formant polymers produced by these procatalysts/catalysts.
Worldwide demand for olefin-based polymers continues to grow as applications for these polymers become more diverse and more sophisticated. Known are Ziegler-Natta catalyst compositions for the production of olefin-based polymers and propylene-based polymers in particular. Ziegler-Natta catalyst compositions typically include a procatalyst containing a transition metal halide (i.e., titanium, chromium, vanadium), a cocatalyst such as an organoaluminum compound, and optionally an external electron donor. Many conventional Ziegler-Natta catalyst compositions include a magnesium chloride-supported titanium chloride procatalyst with a phthalate-based internal electron donor.
The health concerns from phthalate exposure are driving the art to find phthalate substitutes. Known are catalyst compositions containing a malonate or halo-malonate as an internal electron donor for producing propylene-based polymers. The art recognizes the need for additional halo-malonates suitable as phthalate substitutes in olefin polymerization catalysts.